Method of shredding paper and the like



Feb. 13, 1934. w. J. WINSTON 1,947,323

METHOD OF SHREDDING PAPER AND THE LIKE Filed Nov. 21. 1932 A7 TORNEY Patented Feb. 13, 1934 UNITED STATES PATENT OFFICE William J. Winston, Saginaw, Mich., assignor to Mitts at Merrill, Saginaw, Mich., a corporation of Michigan Application November 21. 1932 Serial No. 643,589

1 Claim.

This invention is a'method for making packing material, and it may be considered as a mechanical process whose product is a known article of manufacture, but of superior quality for its 8 intended use. The product of this process is an excelsior-like material in the form of a loose mass of substantially unlaminated and confusedly entwined flexible strips made, for example, from paper such as old newspapers, magal zines or the like.

The finished article possesses certain commercially desirable qualities; notably it contains but few filaments or long narrow strips that overlie one upon another and consequently it is superior, in respect to lightness, looseness and flufiiness, to similar material that heretofore has been produced by means of roll or splitting shears, or by vertical shearing knives. The goods produced by those last-mentioned methods showed 90 much overlying of the strips.

Theoretically an ideal product would have no two strips overlying because that would require double the amount of material without any compensating advantages. My present method yields a product that is quite close to the'ideal in that regard because it apparently introduces into the finished paper strips variant tendencies to curl, warp, separate and fluff 'up rather than to remain fiatwise one upon the other. These tendencies are conceivably caused by the introduction into the individual strips of many indeterminate twisting and warping stresses by the peculiar shearing action which is characteristic of my invention. Another cause of the tendency to separate may be that the severed edges are not perfectly straight, but are slightly curved. A

still further and greatly improved fluffing effect is produced by a novel endwise sliding and radially outward endwise throwing action that is 40 imparted to each newly severed swatch as it leaves the knife that severed it, as distinguished from the conventional sidewise delivery of the swatch in earlier machinesu.

My method of producing the improved product is to repeatedly shear swatches from the end of a tablet-like pack of paper sheets while imparting continuous advancing movement to the pack. Shearing, according to my method, may be described ascommencing at an upper edge of the pack and terminating at the diagonally opposite lower edge. Of course the edges of a pack of old newspapers is not sharply defined, and the term edge is here used merely for purposes of description.

Each individual strip of paper in every swatch severed from the pack in that manner is the result of shearing actions that are slightly difierent from the shearing strains by which any of the other strips in the same swatch are produced, even though they were made by the same stroke 00 of the cutter. This will be apparent when it is noted that each freshly sheared advancing face of the stock pack is a slightly warped surface. Such warped cleavage is evidence of what may be termed a non-symmetrical shearing action. This action imparts to the severed strips of paper a tendency to separate from each other, that is, each strip tends to abandon or depart from its previous flat contact with the adjacent strips. In practice, strips cut in this way have a slight but effectual tendency to curl individually and to become wavy, unlaminated, light'and fluffy, as distinguished from the adhering tendency in paper swatches that have been cut from a pack of sheets by the guillotine-like knife of the book binder or printer, or that have been severed by means of interdigitating roll cutters or splitting shears. Those latter swatches tend to stay together in a laminated strap-like body and are not so suitable for packing purposes.

The present invention may be considered in part as being a new and unobvious way of operating a known type of machine, such as, for example, a cutting machine for chopping up cornstalks including a stock table, a cutter, feed rolls, and knives mounted on a revolving disk. However, those machines were neither intended nor adapted for the attainment of the results described herein.

For purposes of explanation of my method 190 shall disclose only a single practical means for its employment in the manufacture of excelsiorlike paper material from old newspapers or magazines.

Fig. 1 is a perspective view of a preferred embodiment of a machine by which the invention may be practiced.

Fig. 2 is an enlarged cross sectional detail taken on line 2-,-2 of Fig. 1.

Fig. 3 is a diagrammatic view in perspective, showing the comparative shapes of sheared surfaces made by the present method and (in dotted lines) by square shearing.

Like numerals refer to the same parts in the different views.

A stationary feed table 1 is mounted on the frame 2 and at its end is a fixed knife bar 3 that extends transversely of the path of travel of the pad or pack of papers 4 or other material to be worked. The feed is produced by co-operation 110 co-operate with stationary bar 3.

of two power driven rolls positioned one above the other. The lower roll, 5, is mounted in fixed bearings in the frame, and the upper roll, 6, is movable up and down to accommodate different thicknesses of material. Roll 6 is carried in bearings on the free ends of horizontal arms 7, '7 pivoted in fixed bearings 8 on the frame 2. Roll 6 is driven by sprockets 9, 10, connected by chain 11 and gears 12, sprocket 13, chain 14, and worm gearing 15, drive shaft 16 and drive pulley 17. The roll 6 is urged downwardly by spring 18.

Shearing cutters, as for example knives 19, They are mounted radially on a revolvable power-driven disk 20 so as to produce a shearing cut that progresses from an end of bar 3, across the path offeed to its other end. Disk 20 is mounted in suitable bearings in known manner (not shown) and is rotated by belt connection 21 from cone pulleys 22 on shaft 16 to corresponding cone pulleys 23 on the axle of disk 20.

Each knife 19 is received against a beveled face 24 on disk 20, being clamped in place by a backing bar 25 that is supported by set bolts 26 disposed in the plane of rotation of the disk and set bolts 27 at right angles thereto.

In operation, knives 519 are inserted between the beveled face 24 and the correspondingly beveled face of bar 25, and the cutting edge of the knife is positioned in proper cutting relation to the cutting edge ofbar 3. Bolts 26 and 27 are then tightened to clamp the knives in place. An

undercut clearance chamber 28 is provided lengthwise of the outer face of bar 25, underneath the cutting edge of knife 19.

Preferably, table 1, rolls 5, 6 and bar 3 are all mounted on a bracket 29 that is adjustable as a unit toward and from the plane of revolution of the radial knives 19, to facilitate assembling adjustments, and also, if desired, later working adjustments. For adjustment purposes the bracket 29 is provided with screw adjustment on frame 2, consisting of adjusting bolt 30 and clamping bolts 31 and slot connections.

In operating the machine in practicing the method herein claimed, pulley 1'7 is power driven to rotate disk 20 at a speed determined by the selected cone pulleys 22, 23, and the rolls 5, 6 are driven in the direction of the knives, Fig. 2, through worm gears, 15, chains 14, 11 and their associated gears and sprockets.

A pack 4 of old newspapers or other suitable material is placed on table 1 and is fed along the table by means of the power driven rolls 5, 6 toward the cutting edge of bar 3. Roll 6 adapts itself -to the thickness of the material and presses downupon it with the force of spring 18. The line of squeeze between the rolls is preferably somewhat remote from the cutting edge of bar 3 so that the material sheets will not be tightly compressed at the line of cut, but will be loose enough to yield slightly as the cutter passes through and the feeding movement continues, without producing any undesirable binding action against the knives, as is indicated in Fig. 2. The feed is continuous, as is also the rotation of the knives, so that each knife cuts off a swatch, made up of paper strips, from the end of the pack, by progressively shearing from a given corner of the pack, say, the right hand upper corner A in Fig. 3 cross sectionally, that is, along bar 3, to the diagonally opposite lower corner B during the continued advance of the material. Each individual strip that constitutes an element of a swatch is thereby subjected to shearing, stretching and impact stresses that give it a normal tendency to depart from its previous fiat contact with adjacent strips. The clearance channels 28 beneath the knives 19 drive the swatches downward at considerable speed upon a suitable discharge chute 32. The downward and outward or centrifugal throw, in a direction lengthwise of the severed swatch, together with the resistance afforded by the still air into which the swatches are discharged by thus sliding endwise away from the knives, together with their inherent tendency to separate due to the above mentioned warping stresses in the individual strips, serve to break up the swatches into their constituent elemental strips and tangle them into a flufiy mass. A product that is practically free from overlying strips is thus produced and consequently the greatest amount of fiuihness is attained in the resultant improved product.

In Fig. 3, the dotted lines indicate the position of a straight out through pack 4 where shearing is not accompanied by longitudinal feeding move ment. C-A indicates the curved edge produced on pack 4 when the two actions take place together as in my method, and D is the working arc of travel of the knife on the disk 20.

Strips of various widths can be made by changing the belt 21 to another pair of pulleys or cones 22, 23, so as to give a different relation between the rate of feed along table 1 and the rate of operation of knives 19.

Having thus described my invention, what I claim and desire to claim by Letters Patent is:

The method of making a loose mass of confusedly entwined long narrow strips of flexible material which consists in imparting continuous advancing movement under pressureapplied to both top and bottom of a flat pack of material sheets and simultaneously cutting off swatches from the end of the pack by progressively shearing from a given corner of the pack cross sectionally to its diagonally opposite corner during the said advancing movement of the pack, the operative step which consists of imparting to the swatch, immediately upon its severance from the pack as above described, a sliding throw in the direction of the length of the severed swatch and outwardly from the axis of said shearing movement, whereby further separation of the individual strips of the swatcli is attained by air impact on the advancing portion of the swatch.

WILLIAM J. WINSTON. 

